From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergei Shtylyov Subject: Re: [PATCH 1/2] libata: Add two more columns to the ata_timing table. Date: Mon, 08 Dec 2008 21:48:47 +0300 Message-ID: <493D6C0F.7070809@ru.mvista.com> References: <4939B402.9010004@caviumnetworks.com> <1228518561-16242-1-git-send-email-ddaney@caviumnetworks.com> <493ADE48.6050709@ru.mvista.com> <493D65C8.2060808@caviumnetworks.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from gateway-1237.mvista.com ([63.81.120.155]:40016 "EHLO imap.sh.mvista.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1751148AbYLHSsv (ORCPT ); Mon, 8 Dec 2008 13:48:51 -0500 In-Reply-To: <493D65C8.2060808@caviumnetworks.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: David Daney Cc: linux-ide@vger.kernel.org, linux-mips@linux-mips.org David Daney wrote: >> Hello. >> David Daney wrote: >>> The forthcoming OCTEON SOC Compact Flash driver needs a few more >>> timing values than were available in the ata_timing table. I add new >>> columns for write_hold and read_holdz times. The values were obtained >>> from the Compact Flash specification Rev 4.1. >>> Signed-off-by: David Daney >> NAK. >>> diff --git a/include/linux/libata.h b/include/linux/libata.h >>> index ed3f26e..95fa9f6 100644 >>> --- a/include/linux/libata.h >>> +++ b/include/linux/libata.h >> >> [...] >> >>> enum ata_xfer_mask { >>> @@ -864,6 +868,8 @@ struct ata_timing { >>> unsigned short cyc8b; /* t0 for 8-bit I/O */ >>> unsigned short active; /* t2 or tD */ >>> unsigned short recover; /* t2i or tK */ >>> + unsigned short write_hold; /* t4 */ >>> + unsigned short read_holdz; /* t6z */ >> >> >> Sorry for failing to notice this before but t6z is again the timing >> that the host can't control. Therefore I'm seeig no sense in its >> addition. > > > The host cannot control t6z, but in some cases (like ours) it needs to > be aware of its value. We cannot start driving the bus for access to > other devices until the CF stops driving it. We need to know how long > to wait until it is safe to use the bus for other things. Re-read the spec please, the timing you need is t9 and it's much longer than t6 that your driver using instead. >> I don't know how your driver is going to use it -- but most probably >> incorrectly... > Thanks for that vote of confidence. You're welcome. :-) > David Daney MBR, Sergei